1. Field of the Invention
This invention relates to improvements in lifting apparatus and more particularly, but not by way of limitation, to a self-propelled floor jack apparatus for lifting substantially great loads.
2. Description of the Prior Art
Many extremely large off-highway vehicles are in wide spread use today that have been designed for handling large tasks, such as multi-ton ore haulers used in open pit mining, and the like, which carry loads previously requiring many vehicles. These large vehicles greatly increase the speed of ore recovery and reduce the overall cost thereof, which is very important in the industry. However, the large dimensions of the vehicles combined with the great weights thereof render the maintenance of this equipment very difficult, particularly since many servicing operations may be greatly enhanced by lifting the equipment for facilitating access to the portion thereof to be serviced. For example, the tires utilized on these large pieces of equipment are correspondingly large and expensive, and the great weights carried by the tires result in relatively low useful mileage therefor, and normally the tires must be frequently repaired or replaced.
Whereas there are many lifting device, floor jacks, and the like, available today which are adapted for engaging the axle, frame, or the like, of a vehicle for elevating thereof in a substantially conventional manner, the large size and weight of these large pieces of equipment result in the fact that they are not readily adapted to manipulation by the usual present day lifting devices. As a consequence, relatively elemental and crude blocking methods are normally used at present for supporting portions of these vehicles in elevated positions during servicing or maintenance thereof.